民间信仰地域分异的微观分析——泉州三个村庄神祇生态位宽度测量和比较

民间信仰区域分异,前人的研究多数定位于有方言差异的大尺度区域。但无方言差异的小尺度区域内,人们对神祇的信仰和供奉也存在一定的差异。本文利用生态位理论及生态位宽度测度模型对泉州市东海镇三个不同村落(蟳埔、宝山和法石)的民间神祇信仰情况进行微观分析。结果显示,在无方言差异的小尺度区域内,影响神祇在区域内生态位宽度的最主要因素是神祇功能与这个区域产业类型的相关程度。神祇的功能与区域内产业类型的相关程度是影响民间信仰神祇区域分异的重要因素。区域间产业类型的分异受自然地理条件的影响。因此,特定功能神祇的区域分异与自然地理环境有密切关系。由生态位宽度测度模型计算出的民间信仰神祇生态位数据与神祇在三个村落的分布及影响的实际情况比较契合,生态位理论应用于民间信仰神祇的区域研究是可行的。     

浅埋隧道围岩应力场的计算复变函数求解法

对于受地表边界和地面荷载影响的浅埋隧道的围岩应力场,由于在数学处理上存在一定的困难,很难用解析解来进行分析,而通常采用边界元或有限元的数值方法来解答。为了求解浅埋隧道的应力场,采用边界配点来确定边界条件,同时用保角映射将一个含圆孔的半无限空间区域映射为圆环域,然后把这个区域内的解析函数展开成Laurent级数的形式,利用Muskhelishvili的复变函数理论和最小二乘法来确定解析函数的各项系数,从而求得浅埋隧道围岩压力的半数值、半解析解,最后通过算例给出了围岩应力的分布情况。计算结果表明,该方法计算精度高、计算量小,具有应用价值。     

内撑式排桩支护结构的设计优化研究

在分析内撑式排桩支护结构受力特性和设计优化空间的基础上,基于满应力设计基本思想,建立了支护桩－内支撑（节点）部位的设计优化数学模型,提出了用于求解该（节点）部位局部优化解的新的目标函数 和相应的设计优化判据,推导并比较了钢筋混凝土内支撑等效轴向抗压容许应力 和支护桩等效抗弯容许应力 的3种取值方法,并以杭州某基坑支护应用为例作了介绍。可供同类基坑支护设计优化时借鉴。     

A dynamic relationship between the leaf phenology and rainfall regimes of Hawaiian tropical ecosystems: A remote sensing approach

Hypertemporal MODIS time series data provide a unique opportunity to investigate a dynamic relationship between leaf phenology and the climatic pattern of diverse, cloud‐prone Hawaiian ecosystems. Harmonic analysis summarized the complex greenness signals of Hawaiian tropical ecosystems into two main phenological wave forms – a moisture‐limited and a light‐limited type. Greenness maximums occurred during the wet season in dry and mesic ecosystems, and during the dry season in wet forests. The magnitude and periodicity of greenness fluctuations were also rainfall‐dependent. The annual greenness amplitude increased with increasing mean annual precipitation (MAP) in dry and mesic ecosystems. In wetter environments where MAP was greater than 3000 mm, however, annual greenness amplitude decreased with MAP. Annual greenness periodicity was stronger in drylands than in wet forests, and it weakened as annual precipitation increased. This result shows that rainfall is less important as a limiting factor in wet forests than it is in drylands. Therefore, leaf phenology is not governed by rainfall seasonality as forest wetness increases in the region.     

基于生态功能区划的黄河三角洲土地资源优化配置

土地资源的优化配置作为一种手段,其实质是依据土地类型本身的生态适宜性及其结构格局的差异性,运用人工技术调控的方法对有悖于自然生态结构的现状利用结构进行优化调整与安排,从而达到土地利用系统功能趋优的目的。论文首先从生态学的角度,根据黄河三角洲生态区划优化配置原则,对土地资源适宜方向与土地利用现状相匹配,甄别出需要调整的类型,构建黄河三角洲土地资源优化配置模型。其次基于该模型,利用GIS软件分析模块,实现土地资源优化配置。最后采用土地资源利用综合适宜度指数,对黄河三角洲土地资源优化配置效果进行评价,进一步说明了按照生态功能区划原则进行土地资源优化效果很好,具有一定的创新性。     

SSY-Ⅱ石英伸缩仪与SS-Y伸缩仪的对比分析

兰州十里店地震台于1985年安装了1台SSY-Ⅱ石英伸缩仪,于2006年又安装了1台SS-Y伸缩仪。对这两套仪器的主要构造部件——基线、换能系统、标定系统进行了对比分析,并从产出资料的趋势变化、调和分析、干扰、地震事件等方面进行了对比分析,总结了这两套仪器各自的优缺点。     

兰州台阵响应函数及不同方位小地震事件FK分析结果

计算了兰州台阵不同频率的台阵响应函数,对台阵附近不同方位的4个小震进行了FK分析。结果显示兰州台阵2 Hz以下的台阵响应函数在原点附近呈现出对称的单主峰图样,而高于2Hz时台阵响应函数出现较多旁瓣,表明该台阵对于2 Hz以下的信号具有较好的分辨能力。小震的FK分析结果表明,根据甘肃省地震局地震目录和IASP91速度模型计算得到P波方位角和慢度与FK分析的结果总体上比较一致,但也存在一定差别,这种差别可能由所使用的理论模型和当地模型有差别以及未做台阵校正所引起。     

Spatio-temporal interpolation of precipitation during monsoon periods in Pakistan

Spatio-temporal estimation of precipitation over a region is essential to the modeling of hydrologic processes for water resources management. The changes of magnitude and space–time heterogeneity of rainfall observations make space–time estimation of precipitation a challenging task. In this paper we propose a Box–Cox transformed hierarchical Bayesian multivariate spatio-temporal interpolation method for the skewed response variable. The proposed method is applied to estimate space–time monthly precipitation in the monsoon periods during 1974–2000, and 27-year monthly average precipitation data are obtained from 51 stations in Pakistan. The results of transformed hierarchical Bayesian multivariate spatio-temporal interpolation are compared to those of non-transformed hierarchical Bayesian interpolation by using cross-validation. The software developed by [11] is used for Bayesian non-stationary multivariate space–time interpolation. It is observed that the transformed hierarchical Bayesian method provides more accuracy than the non-transformed hierarchical Bayesian method.     

Flow time estimation with spatially variable hillslope velocity in ungauged basins

The automated spatial estimation of the hillslope runoff dynamics is used as a valuable tool for the estimation of the travel time distribution (flow time), a major factor for the hydrologic prediction in ungauged basins. In fact, while the flow time function is usually obtained by rescaling the flow paths with constant channel and hillslope velocities, in this work a spatially distributed kinematic component, as a function of terrain features and in particular slope and land use, is implemented and its influence on the hydrologic response is tested by means of the Width Function Instantaneous Unit Hydrograph (WFIUH) framework. Hillslope surface flow velocities are evaluated by applying different uniform flow formulas within an automated DEM-based (terrain analysis) algorithm. A comparison test of the performances of the Manning, Darcy, Maidment and Soil Conservation Service uniform flow equations is performed for several case studies in Italy pertaining to different climatic and geomorphic conditions. Results provide new insights for a better understanding of the flow time function also introducing a more parsimonious and physically-based calibration scheme of the WFIUH.     

基于双曲正切函数的土动力非线性本构模型

基于双曲正切函数,构造了一种新的土动力非线性本构模型。该模型从双曲正切函数出发,通过平移和缩放构造了土动力应力应变关系的骨架曲线和卸载、反向加载的滞回曲线。相对于其他模型而言,这种新的数学模型参数较少,物理概念明确,形式简单,更利于编程实现,加卸载应力应变关系曲线只需要记忆加卸载转折点处的应力和应变值。将该数学模型应用于场地地震反应分析中,并与常用的等效线性化方法的地震反应结果进行比较,结果初步证明了该本构模型的可行性。